A magnetic compass seeks the magnetic north position by alignment of the compass magnet with the magnetic field of the earth. It is well known that a magnetic compass provides a correct heading indication only when the magnet is in a horizontal position for alignment with the horizontal component of the earth's magnetic field. If the compass magnet is tilted from its horizontal orientation, as can occur during rolling and pitching of a vessel or other body aboard which the compass is installed, or in a high speed turn, the magnet will tend to seek the dip angle and the compass reading will be in error.